1. Field of the Invention
The present invention relates to a process and apparatus for detecting pulses due to electrostatic discharges from furniture or human beings.
2. Description of the Related Art
The present invention concerns the technical domain of detecting brief pulses that generate high frequencies likely to appear, more particularly, in the environment of computer hardware in the general sense, i.e. any system comprising logic circuits for processing data.
Computer hardware is principally constituted by electronic components which, by nature, are very sensitive to mean and high frequencies. It follows that the hardware presents random dysfunctions in the presence of such frequencies. Now, practical experience shows that the premises or environment in which the computer hardware is installed, constitutes a place where high and mean frequencies frequently prevail.
It appears that the high frequencies are generated by brief pulses resulting, principally, from two phenomena. The first relates to the brief pulses of switching in the general sense, coming, for example, from the closure of relays or switches. The second concerns the brief pulses resulting from electrostatic discharges from furniture or human beings.
The state of the art discloses systems for detecting brief pulses, consisting in detecting, via an antenna, the electrical component or the magnetic component of the electromagnetic field generated by these brief pulses.
However, such known systems of the prior art do not distinguish the phenomenon having produced these brief pulses, which represents a considerable drawback, insofar as the technical solutions to be found for overcoming the effect of the brief pulses depend on the phenomenon having generated them.
The state of the art has also proposed, in U.S. Pat. No. 3,790,884, an apparatus for detecting the mean frequency pulses appearing during a storm. This apparatus detects, in a determined geographical location, with the aid of an antenna of 30 meters placed at 7 meter from the ground, the presence of severe storms presenting specific characteristics. This apparatus aims at detecting the maxima and minima of the variations of the electrostatic field developing in the given geographical location. Considering a curve representing the electrostatic field as a function of time, the minima and the maxima correspond to the portions of curve where the slope is zero. The apparatus also ensures detection of an electromagnetic field due, to atmospheric discharges with the aid of a band pass filter centred at a frequency of 455 kHz and with a width of 3 Hz. A severe storm is detected when, on the one hand, fifteen maxima or minima of the electro static field are detected in an interval of time of 1 minute and, on the other hand, when 2800 electromagnetic pulses due to atmospheric discharges appear per minute.
Such an apparatus detects storms in a given geographical location, but is not adapted to determine the phenomenon having produced pulses in a given premises containing computer hardware, due to the very principle of detection and the technical means employed.
The need is therefore felt to have available means for determining the origin of such brief pulses appearing the vicinity of computer hardware so as to employ technical solutions specifically adapted to the phenomena existing in the environment of the computer hardware.